Since their introduction, the number of services and features for cellular telephones has steadily increased while the cost of ownership and operation has decreased. At first, these mobile telecommunication devices operated on analog wireless networks that enabled voice communication and simple paging features. Later, digital wireless networks were introduced for cellular telephones to provide more advanced features for voice and data communication, such as encryption, caller identification and sending and receiving short message service (SMS) text messages. More recently, some cellular telephones enable the browsing of web pages on the Internet or other on-line services.
The functionality of cellular telephones continues to increase. Some cellular telephones incorporate many of the features originally provided for in handheld electronic devices, such as personal digital assistants (PDAs). Relatively simple PDA features such as keeping a list of contacts, a calendar, appointments, and the like have been generally integrated into recent cellular telephone models.
The lower cost of ownership, along with the increased services and features available, has made it common for individuals to own a cellular telephone and use it for daily communications. Individuals are no longer restricting the use of their cellular telephone to strictly business or emergency calls. They are talking with their friends about what they are currently listening to on the radio, watching on television, viewing on the World Wide Web, and the like. The user may want their friends to listen to the same radio or television broadcast they are experiencing, or view the same website they think is interesting. However, cellular telephones do not provide this ability. Instead, a cellular telephone user has to manually change the settings or configuration of their phone, or some other device, in order to participate with their friends in the desired activity.